Pipe-chamfering disk

ABSTRACT

A cutting disk  10  has cutting teeth  16  for cutting through a pipe prior to engagement with the pipe of chamfering teeth  12  pressed or bent sideways out of the plane of a flat body portion  14.  Each of the chamfering teeth  21  defines a cutting edge  18  angled obtusely away from the plane of the plate  14  and from the cutting teeth  16  so that, in use, after the cutting teeth have penetrated the material of a pipe, the chamfering teeth are configured to cut at least one chamfer angled inwardly towards the plane of the cut.

[0001] The cutting and preparation of certain pipes for use (for examplepipes of plastics materials for drainage purposes) presents a problemsince the pies are bulky and difficult to handle and for many purposes achamfer or bevel is required along the cut circumference. For example,drainage pipes of plastics materials are often connected to one anotherby rubber collars or grommets, and a chamfered edge on a pipe isdesirable as it facilitates fitting of the pipe in a collar.

[0002] From a first aspect the invention provides pipe-chamfering diskfor imparting a chamfer to the cut circumference of a cut pipe whichincludes chamfering teeth pressed or bent from a substantially flat bodyportion.

[0003] Typically, the chamfering teeth may be pressed or bent sidewaysout of the plane of the body portion.

[0004] The pipe-chamfering disk may be in the form of a cutting disk,for operation with a tool adapted to spin a cutting or grinding disk,such as an angle-grinding tool or the like. Typically, in use, the diskwill be used to cut vertically in a plane across the pipe axis.

[0005] The disk may be pressed from saw steel, plate steel or otherappropriate, typically flat, metallic material. Preferably the disk istempered or otherwise hardened, Preferably the disk includes cuttingteeth for cutting through the pipe prior to engagement of the chamferingteeth with the pipe; and at least one set of chamfering teeth pressed orbent sideways out of the plane of the cutting teeth.

[0006] Typically each of the chamfering teeth defines a cutting edgeangled obtusely away from the plane of the plate and the cutting teethso that, in use, after the cutting teeth have penetrated the material ofthe pipe, the chamfering teeth are configured to cut at least onechamfer angled inwardly towards the plane of the cut.

[0007] Preferably, though not necessarily, the pipe-chamfering disk hastwo sets of chamfering teeth projecting from opposed sides of thecutting teeth, so that the two sets of chamfering teeth produce aseparate chamfer on either side of the plane of the cut.

[0008] The invention also extends to a pipe-chamfering assembly whichincludes a line-chamfering disk of the invention as hereinbefore definedin combination with a rotatable sleeve for snugly receiving a pipe andfacilitating rotation of the pipe, during operation, by rotation of thesleeve relative to the disk. Typically the sleeve is configured to berotated manually.

[0009] The assembly may include a lock device for checking rotation ofthe sleeve. The lock device may be in the form of a spring-urged balldetent and a complementary recess within which the ball can engage at aparticular datum point in the rotation path of the sleeve.

[0010] This assembly may include two sleeves, to permit relativerotation of separate cut portions of a pipe. Thus one portion may belocked while the other is rotated to achieve a clean chamfer against thechamfering teeth of the disk.

[0011] The base of the assembly may include sturdy extensions (which maybe integral with the base itself) dimensioned and configured to providestability to the assembly, particularly under conditions of use.

[0012] The sleeve(s) of the assembly may be diametrically split and thetwo halves of each arranged (eg by a pivotal connection of the twohalves or the sleeves) to each other) to be separated and married upalong the split at will to permit a pipe to be inserted into andfrictionally engaged by the sleeve(s).

[0013] The assembly may include a drive member for rotationally drivingthe disk, the drive member being mounted in a comparatively simplearrangement adjacent to the sleeve(s) or in register with a slot in aportion of the assembly, so that the disk can be brought into contactwith a pipe held in the sleeve.

[0014] A further aspect the invention provides a method of preparing apipe-chamfering disk which includes the step of pressing or bendingchambering teeth sideways out of the plane of a substantially flat bodyportion.

[0015] It is envisaged that the cutting and pressing process forproducing the pipe-chamfering disk would be carried out in a continuouspressing process. Thus, the production process may involve consecutiveor simultaneous steps of stamping a blank of a cutting disk and pressingthe chamfering teeth sideways out of the plane of the blank.

[0016] The invention will now be described further, by way of example,with reference to the, accompanying diagrammatic drawings, in which:

[0017]FIG. 1 shows, schematically, a side view of a pipe-chamferingmeans according to the invention in the form of a pipe-cutting disk;

[0018]FIG. 2 shows, schematically, an end-on view or the pipe-cuttingdisc shown in FIG. 1;

[0019]FIG. 3 shows, schematically, an exploded front sectional view ofpart of a pipe-chamfering assembly according to the invention;

[0020]FIG. 4 shows, schematically a side sectional elevation taken atthe line IV-IV in FIG. 3; and

[0021]FIG. 5 shows, schematically, a side sectional elevation taken atthe line V-V in FIG. 3.

[0022] Referring to the drawings, a pipe-chamfering disk 10 is in theform of a cutting disk and includes chamfering teeth 12 pressed or bentsideways out of the plane of a substantially flat body portion 14.

[0023] Cutting teeth 16 are provided for cutting through a pipe prior toengagement of the chaffering teeth 12 with the pipe.

[0024] Each of the chamfering teeth 12 defines a cutting edge 18 angledobtusely away from the plane of the plate and from the cutting teeth 16so that, in use, after the cutting teeth have penetrated the material ofa pipe, the chamfering teeth are configured to cut at least one chamferangled inwardly towards the plane of the cut.

[0025] As can be seen in FIG. 2, the cutting disk 10 has two sets ofchamfering teeth 12 projecting from opposed sides of the plane of thebody portion 14 so that, in use, the two sets of chamfering teeth willproduce a separate chamfer on either side of the plane of the cut.

[0026] Turning to FIGS. 3 to 5, reference numeral 20 indicates generallya part of a pipe-chamfering assembly, shown exploded. The assembly 20 isintended to be used in combination with a chamfering means in the formof a cutting disk of FIGS. 1 and 2 (not shown ) driven by a power tool(also not shown) mounted on a central portion 22 of the assembly 20. Inuse, the cutting disk would protrude down through a slot 23 to engagewith a pipe passing through the central portion 22.

[0027] Sleeves 24 and 26 are rotatable with respect to the centralportion 22. When assembled, the sleeves 24, 26 engage with the centralportion 22 in such a way that they may be rotated manually. The pipe tobe cut and chamfered is received snugly in the sleeves and is rotatedrelative to the spinning cutting and chamfering teeth of the cuttingdisk. Once the pipe has been cut through, one portion of the pipe can berotated whilst the other portion is held still, to enable chamfering offirst one cut edge and then the other cut edge of the pipe.

[0028] In order to facilitate holding each separate portion of a cutpipe still whilst the other portion is rotated, the assembly 20 includesa locking device (shown schematically by the circles 28) for checkingrotation of the sleeves 24, 26. These circles 28 symbolise spring-urgedball detents (not shown) which engage with complementary recesses (alsonot shown) at a given point in the rotation path of the sleeves aroundthe central portion 22 to lock the sleeves to the central portion 22.

[0029] The base of the assembly 20 includes sturdy extensions 30dimensioned and configured to provide stability to the assembly,particularly under conditions of use.

[0030] As can be seen from FIGS. 3 to 5 of the drawings, the sleeves 24,26 and the central portion 22 are diametrically split and the two halvesof each part are arranged by means of pivotal corrections 32 to beopened and closed onto each other at will to permit a pipe to beinserted into and frictionally engaged by the sleeves and released aftercutting and chamfering.

[0031] It is believed that the pipe-chamfering means (“the device”) hascertain advantages over previous pipe cutting disks. The present deviceis lighter end less complicated to manufacture, and automation ofpressing process can more simply be achieved than with previous designs.Because it is inexpensive and wears out quickly the device is athrowaway item, and sale of the device will provide a certainconsistency of income since it will have to be replaced frequently.

1. A pipe-chamfering disk for imparting a chamfer to the cutcircumference of a cut pipe, said disc including chamfering teeth bentfrom a substantially flat body portion.
 2. A disk according to claim 1,wherein the chamfering teeth are bent sideways out of the plane of thebody portion.
 3. A disk according to claim 1, in the form of a cuttingdisk, for operation with a tool adapted to spin a cutting disk.
 4. Adisk as claimed in claim 1, pressed from saw steel, plate steel or otherappropriate, typically flat, metallic material, preferably tempered orotherwise hardened.
 5. A disk according to claim 1, including cuttingteeth for cutting through a pipe prior to engagement of said chamferingteeth with the pipe; and at least one set of said chamfering teeth bentsideways out of the plane of the cutting teeth.
 6. A disk according toclaim 5, wherein each chamfering tooth defines a cutting edge angledobtusely away from the plane of the plate and the cutting teeth.
 7. Adisk according to claim 5 which has two sets of chamfering teethprojecting from opposed sides of the cutting teeth, so that the two setsof chamfering teeth produce a separate chamfer on either side of theplane of the cut.
 8. A pipe-chamfering assembly including apipe-chamfering disk for imparting a chamfer to the cut circumference ofa cut pipe, said disc including chamfering teeth bent from asubstantially flat body portion, in combination with a rotatable sleevefor snugly receiving a pipe and facilitating rotation of the pipe,during operation, by rotation of the sleeve relative to the disk.
 9. Anassembly according to claim 8, including a lock device for checkingrotation of the sleeve.
 10. An assembly according to claim 9, whereinthe lock device is in the form of a spring-urged ball detent and acomplementary recess within which the ball can engage at a particulardatum point in the rotation path of the sleeve.
 11. An assemblyaccording to claim 8, including two sleeves, to permit relative rotationof separate cut portions of a pipe.
 12. An assembly according to claim8, including sturdy extensions dimensioned and configured to providestability to the assembly, particularly under conditions of use.
 13. Anassembly according to claim 8, wherein the or each sleeve of theassembly is diametrically split and the two halves of each arranged tobe separated and married up along the split at will to permit a pipe tobe inserted into and frictionally engaged by the or each sleeve.
 14. Anassembly according to claim 8, including a drive member for rotationallydriving the disk, the drive member being mounted adjacent to the or eachsleeve or in register with a slot in a portion of the assembly, so thatthe disk can be brought into contact with a pipe held in the sleeve. 15.A method of preparing a pipe-chamfering disk which includes the step ofbending chamfering teeth sideways out of the plane of a substantiallyflat body portion.
 16. A method according to claim 15, involvingconsecutive or simultaneous steps of stamping a blank of a cutting diskand pressing the chamfering teeth sideways out of the plane of theblank.